Why won't the hinges on my car work?

[Infi_power]

Because hinge surfaces are disabled, So you have to go with new constriants , classic seat and programming

And this video is too old (published in 2016).

And here is the announcement:

Finale of Part Surface Changes: No More Hinges

Hello Devs, Our epic Part Surface trilogy is coming to an end. Last year, we made some changes to remove part Surface behavior, which was about a year after the previous time. As Roblox evolves, there are older features that don’t make sense anymore, have better alternatives, and only confuse new developers. SurfaceTypes and the Joints they create are one of these features. Over the last several years they have lost functionality due to the new physics solver and other updates. We are continu…